A jet plane passes over an aerodrome with a velocity 200 m/s at a height of 490 metre (see fig.). It

constantly blows a whistle of 1 kHz. If it passes over the ground crew, in one second then the change in frequency observed by the staff in this interval will be (if velocity of sound v= 340 m/s)

Question

A jet plane passes over an aerodrome with a velocity 200 m/s at a height of 490 metre (see fig.). It

constantly blows a whistle of 1 kHz. If it passes over the ground crew, in one second then the change in frequency observed by the staff in this interval will be (if velocity of sound v= 340 m/s)

Infinity Learn · Accepted Answer

From figure (13),$$cos$$⁡θ$$=100500=15$$ The frequency heard by staff in initial position n′$$=nvv$$−vscos⁡θ $$=1000$$×$$340340$$−$$200$$×(1/5) $$=1133$$⋅$$33$$ Frequency heard by staff in final position $$nn=nvv+vscos$$⁡θ $$=1000$$×$$340340+200$$×$$(1/5)=894$$⋅$$73$$ Δ$$n=n$$′−n′′$$=1133$$⋅$$33$$−$$894$$⋅$$73=238$$⋅$$6Hz$$

A jet plane passes over an aerodrome with a velocity 200 m/s at a height of 490 metre (see fig.). It

constantly blows a whistle of 1 kHz. If it passes over the ground crew, in one second then the change in frequency observed by the staff in this interval will be (if velocity of sound v= 340 m/s)

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